Data network operators face ever-increasing demands from users. For example, various telecommunications operators provide High-Speed Internet (HSI) service to subscribing customers. The number of HSI customers is growing, and many customers are using HSI service for longer periods and/or for more purposes. Although many operators have systems with very substantial capacity, network bandwidth remains a finite resource that must be shared among numerous subscribers. If one subscriber consumes a substantial amount of bandwidth during a period of network congestion, that subscriber can prevent other subscribers from accessing the network or may otherwise cause degradation of the service provided to those other subscribers. As but one example, a Cable Modem Termination System (CMTS) or other network element may provide HSI service to multiple groups of subscribers. Within a subscriber group served by that CMTS through a common channel, one or two subscribers may attempt to transmit very large files over prolonged periods. The other subscribers in the group, who may significantly outnumber the one or two subscribers sending large files, may only need to send small amounts of data at infrequent intervals. If the one or two subscribers sending large files do so at a time when the network is already congested, the remaining subscribers may experience service-impacting delays. The delayed subscribers will likely find this objectionable, particularly if they and the large-file-transmitting subscribers pay the same price for HSI service.
In the above example, the network operator does not wish to prevent subscribers from sending large files. However, the operator does want to minimize the effect such transmissions may have on other subscribers during times of peak network traffic. In this and in other circumstances, there remains a need for methods and systems that fairly allocate network access among multiple users of shared network resources.